Now I see they are the same. Two days ago they was different.
It's looks like devs changed exe file in github after I posted message about that.
But they not answered why files was different.
Team can modify wallet and fix bugs or integrates new features. I don't know what are differences here but if you always verify the wallet you download, you will be safe.
On the Github of BEAM, the team writes a guide to verify Beam wallet's release binaries
Verifying release binaries
PGP key: "A6C6 2C9F 5593 1860 AFF8 3BBB 997E AB9F 3DF7 F375"
Go to
https://keybase.io/beammw and get the Public PGP key.
Download the signed binary file (with extension .asc) you want to verify.
Verify the signature using PGP Suite or any other PGP verification tools