adverbs - What is the proper construction of this comparative?

This sentence appeared in a recent New Yorker article written by the copy chief there:

I find it easier to use the serial comma consistently rather than stop every time I come to a series and register whether or not the comma before the "and" preceding the last item is actually preventing ambiguity.

Isn't this grammatically incorrect? Shouldn't this be:

I find it easier to use the serial comma than to stop every time I come to a series ...

– deleting the rather and adding a to? Isn't something easier than, and not easier rather than?