This isn't to say domain verification is a bad thing, but depending on how it's done, it's not always the first thing you can tick off on a project.
truly, these are challenging times for spammers
They run SaaS bookings for companies. They (and their clients) want them to come from reservations@companyname.com so people can reply easily to their reservation and go to them. Current options look like setting up something like reply-companyname@saasplatform.com and then have a hook send it to the actual address, which seems like a bit of hassle, but maybe this is the cost of progress on spam.
Asking non-tech clients to configure DKIM/SPF is a problem for them.
And since Sparkpost lets you validate the domain using a DNS record, you can just add it along with the DKIM/SPF.
Yes, they did. I'm the tech guy for a small cultural society, and their emails sent with Mandrill did get dropped by Gmail and other servers before I configured the SPF/DKIM records.
There's a reason why even Mandrill mandates SPF/DKIM for new accounts: https://mandrill.zendesk.com/hc/en-us/articles/205582267-Abo...