A lot of suburban sprawl in the USA doesn’t have good local coffee shops around and Starbucks is the best, or at least reasonably close, option available to get a fancy caffeine fix.

Plus they serve lots of things other than over roasted drip coffee.

I like some of their iced drinks and macchiatos. But I like sweet garbage with too many calories. So my palette isn’t exactly refined. However, that’s a lot of the reason is just lack of options and people genuinely like their sugary sweet drinks and will pay a premium for everybody’s favorite drug caffeine.