It's been a few years since my wedding so let me know if I am missing something here...
I have a childhood friend who is getting married in a month or so. We were close growing up but as adults have drinks a few times a year and chat on social media and attend one anothers events maybe once a year. She told me right away they were engaged but I never expected an invite - one of those might be invited might not but not really invested either way things. No save the date no invitation and it's a little over a month away so my DH and I rightly assumed we weren't invited.
Flashforward to today - we get a pre-printed cardstock stationary in the mail, all done up like a fancy invite BUT with a note saying how the couple had ran the numbers mutilple times but had to let us know we were not going to be invited to their wedding but hope we would keep them in mind on their date. Is this a thing? A ploy for gifts? Just bad taste?
Prior to recieving the "note" I wasn't invested either way but the note was pretty off putting.

Re: Is this a thing now? wedding related
Started fertility treatments 11/2010
Ovarian dysfunction, LPD, male factor
6 failed medicated IUI's
Pregnant 5/2011 - Miscarriage at 6 weeks due to triploidy
Decided to adopt - 6/2012
SURPRISE! Pregnant without intervention - 7/2012
Sweet Baby James Born 3/2013
Decided to be "One and Done"
....OR NOT.
Pregnant 12/2018 despite birth control pills
Here we go again...
Due 8/26/19!
And yes, I see it as rude gift grabby.
My two Angel Babies
Ectopic Pgcy 10/1/11
MC 11/8/12
That's probably the best part - the envelopes were pre-printed and the card stock was NICE - like way nicer than my actual wedding invitations.
Gross.
My two Angel Babies
Ectopic Pgcy 10/1/11
MC 11/8/12
I'm not sure of the intentions but gift grabby does seem likely.
Our Little Raspberry Born 3/27/12
ugh - sorry to hear that. Hopefully you weren't hoping to attend it.
And a big wtf to your niece @PrivacyWanted. He's a half brother so he's not loved as much?
I'm pretty sure it's not a new wedding trend, it's just people being outrageously stupid.
At least I hope.
#2 due 12.23.17
Most likely: This is going to be an awesome party but you can't come!!! So just get me a gift instead. KTHX!
I'm not a big fan of wedding announcements, in general, but it seems like just sending a wedding announcement after the fact would have been more appropriate here.