I'm sure it can be abused, but I wouldn't recommend crying wolf too much. I purchase at least 20 pairs of nikes a year for personal use (work out daily), be it running shoes or hoops shoes, not counting retros and other shoes I get to wear casually and to work sometimes.
I'd say on average I get a pair a year that just has a defect like the sole comes apart with regular use, air bag pops, seam comes apart, etc.
I had a bad year this year, two pairs of Jordan 30's (black pair and launch color) came apart at the exact same flex points after hooping in each for about a week. Sent them back no problems. Kobe AD came apart at toe, sent them back. Didnt have any problems of any of my other shoes. And thats like 4 pairs of Kobe XI, numerous pegasus and vomeros, hyperdunks, jordan 31, etc. No problems, just a few isolated ones.
I don't really worry about getting denied, it's only in these cases of manufacturing defects that I send the shoes back. Good to know it's there, especially for us that purchase a ton of shoes every year.