When I was negotiating my salary with my previous employer the only thing I asked for was more vacation time. They refused and instead offered me an extra $3000 so I could take unpaid time off.

They ended up working me to the bone for 6 months then laid me off once the product shipped.

Little things like this can really give you insight into how a company works. If a company is only willing to negotiate on money then maybe money is the only thing they are interested in.