According to the Strunk & White's The Elements of Style (p. 46)
at the end of a list introduced by such as, for example, or any similar expression, etc. is incorrect.
However, I have seen "etc." in many places at the end of a list starting with e.g. Is it incorrect in today's formal English?
It's certainly redundant. Since by saying "for example" you are making it clear that you are giving only some of the cases, it's superfluous to add that there are more by ending "and so on" at the end.
Those who object are likely to be pedantic, but then, no one's going to object if you don't.
In formal English, the answer is yes. In normal English as typically used by "normal folks", not so much. I doubt that anyone is confused by what is a redundant usage.
The answer that matters is how will your readers react. It would probably annoy me but I am overly sensitive about grammar and punctuation. Years of reading and writing detailed technical specifications will do that to you. My favorite variation of Murphey's Law is, "If there is a way to misinterpret this specification, someone, somewhere, at this very moment, is doing exactly that." But the more typical writing such as shopping lists do not warrant such crankiness.
