[gbcdoj]

which is a mere prayer of thanksgiving before a meal

No, it isn't. Sacrifice is explicitly mentioned.

P: Orate, fratres: ut meum ac vestrum sacrificium acceptabile fiat apud Deum Patrem omnipotem.

S: Suscipiat Dominus sacrificium de manibus tuis ad laudem et gloriam nominis sui, ad utilitatem quoque nostram totius que Ecclesiae suae sanctae.

"sacrificium de manibus tuis" is a clear reference to the Eucharistic sacrifice of Christ, as opposed to the "vestrum" sacrifice of praise and thanksgiving.

P: In spiritu humilitatis et in animo contrito suscipiamur a te, Domine; et sic fiat sacrificium nostrum in conspectu tuo hodie, ut placeat tibi, Domine Deus.

[ultima ratio]

There is no mention of PROPITIATORY sacrifice. The Novus Ordo concept of sacrifice is not the traditional Catholic concept. It is the modernist re-defined sacrifice--of thanksgiving and praise for our salvation. Yippee. Protestant through and through.