Morgan and Hales decided not to be a part of the tour party due to security concerns in the wake of a militant attack on a Dhaka restaurant that left 22 people dead in July.
The England and Wales Cricket Board said wicketkeeper Jos Buttler will lead the ODI side in Morgan's absence.
But, Walsh, who flew in on Sep 3 to take up the job of the Tigers' bowling mentor, is not amused.
"Well, a little bit surprised with the tour going ahead…but they've got their personal reasons I'm sure," Walsh told BBC.
"But in terms of cricket, as long as the tour is going ahead, you want to have everyone involved and the best people on the tour.
"I'm sure the Bangladesh fans will be a little bit disappointed and probably some England fans as well, but as long as the tour goes on everybody will be happy,” he added.
The Caribbean legend thinks an incomplete squad on a tour is hard to appreciate for the rest of the players in the team.
"If I'm going on a tour and some of the guys pulled out…you're going to feel a bit disappointed that not everybody going on the tour together.
"Obviously from a team perspective, the team would like everybody selected to go on the tour to have a full squad of those who were selected."
The Jamaican, however, is confident that Bangladesh can provide the tourists with proper security arrangements.
"Yeah, I received reassurances…over safety and security. I felt safe and confident when I was here. I felt, they'll look after us.
"When you weigh up against what's happening in the world - I mean things are happening all over and you weigh your options and your chances - they gave me reassurances of security of the highest level and that's one of the reasons I'm there…"
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