Why isn't the arresting hook always used on land?
There is a lot of stress placed on the airframe when you use the tailhoook. You can see the skin buckling in the picture below behind the landing gear. I'll admit, you probably wouldn't land intentionally with this sort of technique on land but if you catch the wire during the flare it could probably pull you down pretty hard. For these types of landing and it would be difficult to get it right every time.
(Like  I wrote in the comments, I do realize that the aircraft below has not yet caught the cable. When you flare, and you might catch the cable mid-air if you have a nose-high attitude, and slam down hard as it pulls you backwards and you loose lift, or you do a non-flare like carrier pilots, also very hard. IMO I think either would end up like the landing below.)


You have no ability to control the aircraft and you end up stopping and rolling backwards on the runway. You can only be one aircraft at a time and you cannot roll off straight away, wasting time.

You'd have to have an arresting gear system and along with that more staff and maintenance.

At least on aircraft carriers, I believe the arresting cable has a limit of only 250 catches for safety reasons. Even if it the limit was greater on land, you'd have to have people changing the cables on a regular basis.

You'd still have to have conventional brakes which you could just as well use.