The price of video games hasn't changed much over the years. In 1991, my dad wanted Final Fantasy II (now known as IV) for our SNES the day it came out. He even had it pre-ordered, back at a point in time where such things weren't as common as they are now. It cost $65 dollars, which is about the price I'm paying for DAI.
If I was to believe some of the logic in here, that game had to have multiplayer to justify the cost, especially over 23 years ago. That it must be the only reason for the cost, nothing to do with buying a game brand new.
As far as the topic goes, from what I can tell, plenty of folks did ask for DAMP. I am not one of those people, however I don't see the issue. The cost of this game is the same cost I paid for other new games over the years, such as the GoW and Arkham series. I can list more games from over the years that had a $50-$70 price tag, that never had the words "multi-player" attached to it.
If one doesn't have faith in BioWare that the MP will not affect the SP, or much faith in BioWare at all, then I have to question what they are doing here. To complain? Okay, venting is healthy, sure. To ask for exclusion? I can't see them doing that.
For my part, I'm glad that it's available to those that want it. I might even check it out myself down the road. Yet, I know in my heart that BioWare learned their lesson after ME3 with the MP. They won't let the MP affect my SP game.
I got into the ME series earlier this year, so I can only speak as a newcomer, that's coming in after EC and after the War Assets patch. With that patch, MP has never affected my SP game in ME3. Not once and I've played the series three times now. That's the supposed "devil" when it comes to MP affecting SP and thanks to patches, I don't care. The only way MP seems to affect my SP is on load up, when it's connecting to EA automatically. Otherwise, I don't have to acknowledge it's existence.
Finally, even if they were to charge for MP maps (which I really hope they don't do,) then why should it bother anyone else? I don't feel like I have a gun to my head with EA demanding that I must buy all of the microtransactions and DLC that's available. MP wouldn't be any different.