Not sure what about my post prompted your train of thought about first skids. You have an unusual mind, but I'm finally starting to get used to it, after a year and a month of being here on EO.
I say that in all friendliness.
Can't speak for others, but I rarely have a skid all the way up tight behind the seat. I usually have a bit of space, even with two skids. I have 109" of open cargo space before a third-width bulkhead on the driver's side, in front of which is storage and enough room to recline my seat fully. That's changing in the next few days though, to allow a longer cargo area.
Though with what I have now,
or what I will have soon, I always secure whatever I'm carrying for cargo, no matter how close to anything it might be. Usually a couple straps, crossed in an X over the load front to back, starting in front of a 2x8 in wood-beam sockets so the 2x8 is strapped to the skid, in effect. Learned some of that right here on EO.
First guy I ever ran for said "Only
two things I want you to remember, and you'll work out fine here: 1. Don't back out on a run you've already accepted, and 2. Always secure your cargo."
Just a good habit to have, far as I'm concerned. I rarely ever have loads which are so cubed and solid and one piece that I wouldn't worry about it not being strapped, or about it moving in a sudden stop or hard turn. A lot of loose items in bins with no tops, shrink-wrapped boxes and parts, odd-sized items on skids, etc. The more secure it is, whether up against a bulkhead or seat back or not, the less I have to think about it when rolling and the less likely it will cause harm to me, or damage to itself, even in a moderate accident. If it were tight up against a solid wall, like in a trailer or box truck, and the load was full width, that's a lot different.
Bad accidents of extreme impact speed are something else, too. Even then, though, at least as far as I'm concerned, having a load secured is better than not having it strapped down at all.
In other words, what Xiggi said
And, because I don't have a passenger seat, when hauling someone around like my aging mother, I strap her down to the floor in back so she doesn't tip over and roll around. She doesn't like it much, but I tell her it's for her own safety.