they're inept, I think

the part that pisses me off the most is that when I asked whether they cared about sharing before we got the service they said yes, you have to pay extra per extra machine connected and they'd set it up etc. So my dad didn't want to break any rules, so we agreed to that. Well when their people come to do their work, they try to set it up.
We already had a network with a simple hub. They tried plugging the cable modem into the uplink port. All their work went to no avail and they never figured out how to set it up so we said ah screw it, and did it ourselves. We used Sygate nat server software for a while, then bought the linksys router.

is it possible that some user agreement might have provisions for this kind of sharing and they could use that against us?