I've been a member of their slot club from the day the casino was founded. I've never gotten a single piece of mail from them--when I was a local, or when I lived elsewhere. I've asked them why several times. I've never gotten a coherent answer.
Likewise, I've never gotten a single email from them. I DO get occasional offers, and I find out about them only by calling my casino host (who oscillates between being Nancy Nice and the Wicked Witch of the South Strip), and a couple of times, by finding I had free rooms available when I called to make a reservation.
They do seem to have what I call Palmsitis. For most of the years of the Palms' existence, they struggled with the question: are we a locals' casino or not? Consequently, they always blew hot and cold--sometimes very generous to the locals, other times obviously courting the tourist crowd. SP might be trying to throw locals a bone with this mailer stuff, much as Stations (and Boyd too?) now have multiplier days "for invited locals only."
It's all part of the ongoing message Vegas is sending to visitors, "Show up, and we'll charge you a fortune and kick you in the nuts, but we know you're coming anyway, SUCKERS!!!!" Not great as a promotional slogan, but refreshingly honest.