blw2 said:
sometimes folks talk about it being even a bad thing to do (ground loops or some such thing)
To steal a line from the old Highlander TV show: "There can be only one!"
In your stick's and bricks, the neutral and the ground are bonded together in the main fuse box. This is so the safety ground (third wire) has someplace to conduct any stray or leaking current to. Without this bonding, it would provide no safety at all.
If you had a shop or barn or something like that on your property, and you ran power to a separate fuse box in it from your main box, that would be a SUB-Panel, and the electrician would BREAK the bonding strip between the neutral and ground in it. If he didn't, you MIGHT have those nasty ground loop problems. The third wire between the main and sub panel gives you your electrical connection back the the bond in the main box.
On our RVs, the main fuse box at the campground has it's neutral and ground bonded, and the fuse boxes in our RVs is considered a sub-panel of that, so again, it's not bonded. With a built in genny, the transfer switch takes care of the bonding when it switches over.
Free standing gennies can go either way. If they expect you to use it to power your house during a power outage, it's usually not bonded, because the fuse box is, and as I said, there can be only one.
Hope that clears it up a little for you.