I'm sure you don't.
Trainers and match directors have the opportunity to observe who knows how many rounds go down range every year. They see crap that most of us won't, because those particular malfunctions are rare.
I have seen different types of gas blocks fall off, barrel nuts loosen, fiber optic sights melt, Rem 700 bolt handles come off, scopes break, mounts loosen, nosedive problems, bolt over base problems, mag seating problems, ARs doubling, etc, etc. That is with just a few years of match experience. There are fixes to these problems, some cheap, some pricey. It may be better for some to live with the risk of a brazed on bolt handle instead of getting a bolt machined from a single piece of steel (Surgeon actions, Nesika Bay, etc). Just because you don't know something doesn't mean it doesn't exist.
Why did Mag-Pul design and refine their anti-tilt follower if there was no problem with the green followers? How would you design a floor plate if you had witnessed the retention tabs getting bent and broken? How much would it cost to have metal followers and floor plates made for low volume production runs to solve a problem that may only manifest once in 5,000 rounds?
These mags have a reason for being, if you are happy with USGI great.