The “too” would need to be isolated by commas to be correct. I should definitely be using commas. But commas also represent pause in speech and sometimes that is the only reason for them being used in a sentence. I know people do say ‘too’ at the end of sentences. I did that too. It has pauses too. Maybe they are correct, but we are still doing it. Though both would be understood and neither is “wrong” to any prosecutable degree, I’d stick with the “too” at the end for fluency.

Where it takes so long to make a comma count, many people don’t use it at all. Is they really used when they are needed? If you read a sentence aloud, and put a comma where there would be a natural pause, you should be all right. Why do some people ignore the commas in sentences, instead of searching for meaning on the page? When they read the sentence to themselves it seems fine. Without any commas, they forget to realize that the reader may not put the emphasis in the same places without commas. The other one that they should avoid is, for instance, The Old Testament. What is a failure responsibility by the speechwriter.