For a start, farmland works well with green friendly cards - silk road, scout, farming village, cross roads, hoard, venture, adventurer, etc. Where a silver isn't that great or may even clog things up (if I'm running a lean venture deck I don't want silvers stopping my venture chains early).
For a bigger thing, don't overlook the value of trashing estates & coppers for better cards. Strong 2's & 4's make farmlands much more valuable (for instance getting a village out of an estate and having province bait in deck can be quite helpful). Or consider a swindler game, buying farmland lets me turn my 4th chancellor (in a no +actions game) into something useful (like a royal seal) and if my opponent swindles the farmland I don't care - he can only give me something better.
Other concerns:
Silver is vulnerable to thief, noble brigand, and ghost ship while farmland is not.
Farmland can be fed to something else next turn (e.g. a salvager) while also allowing the remodeling of another card. E.g. buy farmland, turn a village into a festival ... apprentice a farmland for six cards. This is almost strictly better than gold if you are certain of trashing your 6 coin purchase for benefit instead of playing it.
Bridges, highways, etc. can allow for fun hijinx - eg. a TR/Bridge lets you turn coppers into TR. It is also a good bit easier to get farmland down to marginal prices and spam it.
Farmland can work well as a late game tie breaker - a hand of S, S, S, G, Estate can become +8 points instead of +6.
However, going back to your narrow scenario - using every farmland remodel to remodel a farmland. Well lets look close at that. Say you have an empty hand the first time and some engine that allows you to always have the previous farmland up for remodel (say scout/cross road). With a farmland your VP totals climb up:
2, 8, 14, 20, 26 (game ends)
Without farmland:
0, 6, 12, 18, 24 (game ends)
So in the case where you always purchase farmland and always remodel farmland to a province, then you come out 2 points ahead instead of buying treasure.