Eventually you'll manage to counter that move because shovellers rely on the strength of the opener more than their actual skill. Ultimately the player hurts themselves in the long run, and you start managing to twist his momentum to your advantage.
Unless you don't want to wait that long. Then just mess around in single player till you find a counter move. But getting a feel behind the physics of it is smarter.
I am completely OK with it. My main problem with people having problems with shoveling, is that a shovel is just a basic version of a lift so there really is no point at which you can draw the line for what is a shovel and what is a lift.
Also, a shovel can be easily beaten. If you fuck up the opponent's footing, they will just shove themselves out of the dojo.
If someone tries too shovel you and both your hands are held to their hands, extend both pecs, elbows, contract both wrists and raise both shoulders.