I've worked on a few loyalty programs of Forbes-500 type companies, and the short answer is yes, definitely.
I clearly remember one company actively monitoring points collection to identify outliers (i.e. people who went through the trash collecting barcodes for points, etc..) to ensure they weren't becoming unprofitable program members. If the person crossed that threshold, the program would take actions to slow down or limit their redemption (i.e. limit the number of points redemptions which one account can do in one 24 hour period, etc...). They usually wouldn't kick the person out of the program as that action had the potential to generate bad press, and it was usually relatively easy for the person to just sign up again using different information. Limits, on the other hand, actually limited or prevented the "abuse" activity without hurting the "good" program members.
BTW, my favorite part from the article:
David approached the local Salvation Army with an offer; if they gave him a bunch of volunteers to peel off all the bar codes on his pudding, he’d donate the pudding to them. But here’s the beautiful part, doing this counted as a considerable charitable donation, which let David claim just over $800 back in tax deductions at the end of they year.
I work with a guy who obsesses over air miles. This year he took his family to Europe for free (including hotels). So it is still doable, but it takes a lot of work. He has about 20 credit cards and is constantly cancelling and applying for new cards. I would argue that my coworker is probably spending way too much time and if you take into account opportunity costs it probably isn't worth it for him. But I suppose if he enjoys it and sees it as a hobby, why not?
I would say that a lot of the financial business does something similar; exploit a loophole to make a windfall[0]. The benefits your friend gets might or might not be worth the time, but my ideas about this are pretty much: you shouldn't take from the system more than you put in. A lot of people work to make this well oiled machine work the way it does; and if you don't do something productive, you're kinda just leeching off it.
