At that, Target is
And I wasn't bannedI just get the luxury of buying as much as I want, but I can't return/ exchange
Might as well be banned, eh?
I'm sorry you received this letter as a loyal customer who didn't do anything wrong.
However, do keep in mind that you're not banned from returning or exchanging -- only from doing so without receipts. I also think they handled it the right way by asking you to call them -- if you can discuss with them why you had a large number of returns without receipt in 6 months, they may decide that their letter cast too wide a net. I understand if this turns you off to Coach and you don't want to call them, but it sounds like they realize there may be circumstances when someone does have a legitimate reason for these types of returns.
That being said, I think Coach is doing a good thing by bucking down on things that raise a red flag in their systems. Every time there is a return without receipt, their risk of taking back a fake bag or a stolen bag increases.
Coach's official return policy requires a receipt or the online packaging. Although they've been lenient with you with their policy, they have the right to enforce the policy, esp. when they determine that your returns without receipt have been excessive.