The US domestic F standard (and in particular for DL) is not that you "wait for them to find the time to ask you", though of course as with most airlines sometimes you get better FAs and sometimes not so much. I'm not going to defend the salad, though. DL used to have pretty good food prior to the pandemic, but then cut it pretty deeply.

There are no DL domestic F configurations with 8 rows of F, the configs are 12F (3x4), 16F (4x4), 20F (5x4), and 24F (6x4, only on the 757-300 of which there are relatively few in service), with 9F (3x3) or 12F (4x3) on the regionals. In most configs, there is one dedicated F FA, and one "floater" who assists with the F service before moving back to Y. One of the major benefits of the wider seats (which also generally have pitch of 36" - 38", better than CE) is that there is no middle seat for anyone to move into. Most of the reason I book CE is for that extra space (well, and TP accumulation), I'd be pretty livid if somebody took it over and would probably ask them on the spot to reimburse me for the extra cost of my ticket (obviously not expecting that they would).