Comment 1 for bug 1663376

Thank you for your report Alexis and your help to make Ubuntu better!

I can confirm the issue.

There actually is som ecode that I think should make it a recommends, but it isn't:
cat debian/php-snmp.substvars.extra
php-snmp:Recommends=snmp

Yet in the debian/control file it does not reference the substvars.
That said it likely needs something like:
  Recommends: ${php-snmp:Recommends}

I checked and Debian has just the same issues with it.
THat is still true with latest php7.1-7.1.1.
Since this bug is present in Debian too it would be best fixed in Debian as well, and then Ubuntu will pick it up on the next merge.

Would you mind filing a bug with Debian please and mention the bug number you got here?
From there we can look into SRUing it back to released versions.