I have landed at several hotels recently, one of which said they would charge a landing fee, but I could use that as credit against anything. In the end they didn't even mention it. (Priory Bay on IoW)
Another just the other side of the Severn Bridge (name escapes me for the second) didn't charge anthing and came and picked us up from the H in a minibus.
The third (Pale Hall, also in Wales) was very accomodating though we were there for 3 days (but in and out quite a lot) and obviously no landing charge (though the bar bill was quite a lot
)
The fourth (Whatley Manor) cut the grass and faxed me a map, no charge (but again was staying there)
Like TOT says, they don't charge for car-parking, its hard to justify a landing fee when they provide nothing. My policy is if they mention it, and it is > 0, then thank them politely, turn them down and find somewhere else. There are a lot of hotels out there!