If my parents are paying my college tuition but not claiming me on their taxes, can they use the 1098-T form on their taxes ?

No.  The student is not a dependent on their tax return then they cannot claim any education expenses or education credits on their tax return.

If you are not  their dependent, you can claim the tuition credit, even though they paid it..

But a full time unmarried student, under age 24, is only eligible for the refundable portion of the American Opportunity Credit if he supports himself by working. You cannot be supporting yourself on parental support, 529 plans or student loans & grants. You usually must have actually paid tuition, not had it paid by scholarships & grants.  It is usually best if the parent claims that credit. 

If you do not have enough income to  get a tax benefit, from a tuition credit, maybe you should look at why your parents are not claiming you.  For example, if it's about the stimulus payment; they can claim you this year and you get the stimulus next year.  

"In essence, the stimulus check acts as an advance of your 2020 income tax refund. This means when you prepare your 2020 income tax return, there will be a line to include the section 6428 credit. The credit on your 2020 return is subtracted by any amount received as a stimulus check in 2020. If the amount you received as a stimulus check is less than the credit you are due, the difference will be included as part of your 2020 refund. If you have been overpaid by receiving the stimulus check, however, you will not be required to return any excess amount".