Yes. Unless they said otherwise in their TOS.
"Thank you for reaching out and providing us with the opportunity to clarify. We welcome and accept employees with all political beliefs at Grubhub, no matter who they voted for in this or any election. We do not discriminate on the basis of someone's principles, or otherwise. The message was intended to advocate for inclusion and tolerance -- regardless of political affiliation -- during this time of transition for our country.
Thank you, Grubhub"