The orgs that don't respect that (Medecins sans Frontieres comes to mind--multiple glossy mailings per year) get removed from the list. It's kind of harsh, but there are plenty of deserving orgs to support who are compatible with this stance. I understand why, in general, such outreach makes sense, but in my specific case, I find it annoying and it doesn't motivate me.

I've found the Against Malaria Foundation to be stellar in this regard. They were very responsive in getting set up to accept Canadian stock when I inquired about it. They did one unexpected followup communication, but it wasn't a solicitation. Instead, they were considering changing how stock donation would work in Canada in order to minimize their fees, and wanted feedback on whether it would be a good or bad change from the perspective of a donor. They were explicit that the feedback was optional, and that they weren't soliciting a donation, just effectively doing market research.