That's not to say that memes don't sometimes have associated "fields" of influence. For example, one might generalize the concept of a "reality distortion field" to cover all kinds of memetic influence. The "reality distortion field" that surrounds some cult leaders is a potentially-useful concept that could potentially be quantified and given a scientific basis.
However, the biggest problem with memetic fields is that memetics isn't ready for them yet. Maybe if memetics was decades-old orthodoxy, we could consider the idea of some Sheldrake-free memetic fields with a straight face. However that isn't the current situation - and "memetic fields" just sound like too much of a joke at the moment. The term "field" sounds like it comes from physics - and a "memetic field" conjours up some kind of metaphysical emanations from memes. Just the sort of thing that Rupert Sheldrake would love.
I think we should skip the "memetic field" concept for now. It seems like just the kind of fringe science that could potentially give memetics a bad name.