Graphic design services in the United States are a pivotal, multi-faceted field that employ a convergence of art, technology, psychology, and business strategy to create visually engaging and conceptually compelling designs. The services rendered by these graphic design firms are characterized by a variety of specialized tasks, including logo design, website design, product packaging design, advertising, and branding, amongst others.

A deep dive into the modus operandi of these services reveals a structured and intricate process beginning with understanding the client's objectives, followed by brainstorming and conceptualization, creation and execution, and feedback and revisions. This step-by-step approach ensures that the final outcome is not just aesthetically pleasing, but also aligns with the client's vision, brand identity, and business goals.

The foundation of this process is rooted in a comprehensive comprehension of the client's brief. This involves the confluence of the client's vision and the designer's comprehension of the same. Designers typically conduct exhaustive interrogations to grasp the subtleties and nuances of the client's requirements and expectations. This initial client-designer interaction, often underestimated, is as crucial as any other phase in the design process.

Following this, the design team indulges in brainstorming sessions, research on market trends, competitive analysis, and conceptualization. Here, the creative juices flow as designers combine their artistic understanding with industry knowledge to come up with potential design concepts.

Next, the hands take over the mind's work – creation and execution. Herein, the designer uses various software like Adobe Photoshop, Illustrator, Sketch, and InDesign to bring the conceptualized design to life. Depending on the brief and the design mode, designers might also use traditional methods like hand-drawn sketches. It's worth noting here that the choice of technique often becomes a trade-off between authenticity and convenience, between traditional art's rawness and digital design's flexibility.

After the execution of the design, it is sent to the client for feedback and potential revisions. This phase is often a recursive one, going back and forth until the design meets the client's satisfaction. The rationale behind this iterative process is to ensure that the design aligns with the client's vision and simultaneously appeals to the target audience.

Furthermore, the field of graphic design is influenced by various socio-cultural, economic, and technological factors. For instance, the minimalist design trend, characterized by the use of simple shapes, limited color palettes, and ample white space, has gained popularity in recent years, reflecting societal values of simplicity and clarity. From an economic perspective, brands are leveraging graphic design to differentiate their offerings in a crowded market and elicit emotional responses from consumers, employing principles of behavioral economics.

On the technological front, advancements such as virtual reality (VR), augmented reality (AR), and 3D design are shaping the future of graphic design in the US. These technologies offer new ways to tell stories and engage consumers, creating immersive and interactive experiences. However, the adoption of these technologies also presents challenges. For example, the cost and complexity of VR and AR technologies can be prohibitive for smaller firms.

In conclusion, US graphic design services are an intricate amalgamation of art and technology, governed by a structured process to create designs that resonate with the target audience and align with the client's vision. The choices made during the process, whether it's the design techniques used or the feedback revisions, all stem from the fundamental principle of delivering value to the client and the end consumers. The field continues to evolve, shaped by societal, economic, and technological shifts, revealing an exciting and dynamic future.