Swasti (Su asti - good is) is for welfare of all, humans and other living beings, without any exception other than what is for food.
They said 'Jeevo jeevasya bhojanam" (one life form is food for the other - Srimad Bhagawat Purana, Dharma-Vyādha prakaran).
They also said: "Brahmarpanam brahmahavih brahmnahutam, brahmaiva tena gantavyam brahmakarma samadhina" (the spoon with which the oblation is given is Brahman, and the offering too is Brahman, the act of offering is the act of Brahman, the person who performs this act of Brahman has Brahman as his goal - difficult translation, but I think I got is right this time. See the difference with Prabhupada translation) - BhagawadGita, Chapter 4, Verse 24).
* In layman's language, the eaten is Brahman and the eater also is Brahman. The killer is Brahman and the killed also is Brahman.
And finally they said "prapam datarantarishurjanno dhehi dwipade chatushpade" (O universal giver, give such food which creates energy in the two-legged as well as four-legged - YajurVeda, Chapter 11, Verse 83).
I wrote this to defend non-veg. food. It is not a crime or sin. But I agree that if one can do without it, it is always better.
Don't think that I know all these mantras by heart. I am no pundit. But I know where to search for things like this and do it quite quickly.