Two at the Same Time

On a real estate discussion board someone with the sign-in name BriGuy23 asks, Does anyone on here find any issue with submitting two offers to buy two different apartments at the same time? My friend thinks that its unfair due to the fact that one of the offers is definitely going to not go through which means theyre tying up the sellers time (and money in a way). From a sellers standpoint, I think I would be annoyed but I really dont see anything wrong with it from a buyers perspective. Thoughts?

A response comes from the online-named middle-aged mom: Sellers can negotiate multiple offers so there is no reason why a buyer could not make multiple offers on different places. Assuming you are represented by a buyers agent, I would use the same agent to make both offers. Make certain that your contract gives you an out in the unlikely event both are accepted.

Question: What would your advice be? Justify in ethical terms.