I may be somewhat uniformed and I hope I don't embarass myself here, but..........
In a work-a-day kitchen, polyurethane is the only practical finish. Except for period furniture and musical instruments, varnish is not used anymore, although I have to say that I have not heard of 'conversion vanrnish'. Polyurethane can be obtained in any sheen (matte to gloss), can be water or oil based and can be applied over any well prepared surface. It is scrubable, resistant to just about all ktichen liquids and can easily be touched up in the future.
Laquer is really for 'look-but-don't-touch" furniture; both brushing and spray laquers. Their surfaces are easily stained, they are hard and brittle and laquer is always soluable in its laquer base. Again, I'm not really familiar with Acrylic Laquer, except that I think that is the new laquer base for spraying custom cars.
Like I say, I hope I'm not out in left field here.....but please don't hesitate to tell me if you think I am.....I'm always interested in learning more :-)