We've been there before and know that we can easily score a free buffet at the Horseshoe by asking the pit boss while playing blackjack or by sliding our card through the machine at the Player's Club. In the past when we've stayed at the Horseshoe, we've gone to a casino host before we check out and humbly asked if they could comp anything off our stay and usually get 1 night free and other minor charges credited off (we consider ourselves low rollers - but we usually do stay for 4 or 5 nights). With that method, we have 2 free nights at Gold Strike, 2 free nights at Horseshoe - and could have 3 free nights at Sam's Town.
I already know about the traditional way.get a players card, use it - and then have offers mailed or emailed to you.