UpToDate has a couple (1) (2) pretty good articles discussing current research and recs on the use of endoscopic ultrasound (EUS). As it is behind a paywall (which some hospitals pay for, so you might be able to access it at a local institution), Medscape has a couple good articles as well (3) (4).
I cannot accurately speak for national or international standards of practice, but your question asks for an individual's viewpoint from primary care in the US or UK, and is specific to gallbladder disease. From my experience in the US, the standard of practice for outpatient primary care management of non-emergent suspected gallbladder disease remains to start with transabdominal ultrasonography with liver function tests. I have very rarely seen EUS be ordered in the primary setting, and never yet as the initial test.
This is likely because although EUS is more sensitive and specific than transabdominal ultrasound, it is more invasive, costly, difficult, time-consuming, requires sedation, and risks are - although fairly low - still higher than transabdominal US. Thus transabdominal US is a more reasonable first step, with the knowledge that it is not 100% sensitive and thus additional testing is required for high suspicion. In that case, depending on the suspected pathology, additional testing is ordered and sometimes referral made to a gastroenterologist or general surgeon.
A gastroenterologist's practice may be different, however. And of course ER/inpatient management is different due to patient acuity, but in most cases, transabdominal is still the initial test. Again due to lower sensitivity it is not sufficient to rule out if suspicion is high enough; however, if it does find something, it provides a quick answer.
This is not a comprehensive discussion on its use, but it addresses your primary question. I would be interested in hearing from practitioners in different locations if EUS is more broadly used in primary settings.