If you want to pay some company to grade/slab/authenticate your collectibles, have at it (at your own expense and risk).

If you prefer to purchase collectibles that have been graded/slabbed/authenticated, have at it (at your own risk).

If you do NOT want to do the above, have at it. You may miss out on buyers/sellers that prefer graded/slabbed/authenticated items, but that shouldn’t bother you as many collectibles won’t have that done to them.

That’s my personal 2 cents (and worth every penny).