Reverb is a 'get out of jail' card for a lot of vocalists - it can hide bad breathing, tuning issues or loads of other things (in the wrong hands). Maybe she thinks it'll do the same for the bass; that may be her only frame of reference.
I remember recording an album with an artist and I'd put the bass down, then I played some Hammond on it too. The artist heard it and said that there was something in the bass that he didn't like (it was a bit too 'dirty', so I suggested a different bass tone so we went for that. A quick rerecording later he still wasn't happy when I sent the demo off.
Turns out that the 'dirty bass' bit was coming from the Hammond, not the bass guitar.
Just because someone doesn't have the technical vocabulary, or experience of which instrument makes which noise doesn't mean that they are wrong, just ill equipped to communicate in this particular sphere.