I think altcoin and alt token are almost the same. Alt token is like the testing field and the Altcoin seems the official release.
No they're not the same and yes you're correct when you say some projects make use of Alt-token as a testing phase or perhaps you can say they make use of already existing blockchain to launch their project so they can reach more audience and possibly get listed on more exchange especially DEX. People prefer to invest in Ethereum based project more than projects launching an ICO with their blockchain.