Handheld card readers are price competitive, or at least marginally more expensive. I’d attribute it more to the time investment of switching POS systems.
Everything is weird in the US so can't tell how different it would be, but in Chile you can get a handheld personal car reader [1][2] for around ~25USD to 50USD, even if they needed something more specialized I really can't see them becoming prohibitively expensive, even the matching POS from the same company is just like 400USD[3]
I can get the same deal here if I look for it, nothing special about Chile, etc. Most restaurant/business owners aren't tech savvy and will switch when their equipment fails, not to keep up with tech trends.
