Shewmake is a real prospect you develop him. If they want to get a guy for the minimum they will resign culberson.
Lots of people underestimating how big a change is coming with the minor league contraction that's on the way - players are going to spend less and less time in the minors moving forward. We've already seen this to an extent, and that's before contraction. With everyone looking to slash payroll there are going to be that many fewer spots available for the same OLD marginal (at best) veterans to sit at the end of the bench. Everybody has already seen everything that the Culbersons, Hechavarrias, Tomlins, Scheblers, and Sandovals of the world have to offer - if they're willing to sign split-deals and hang out in Gwinnett in case you have an injury and need someone to fill-in in case of a significant injury that's great, but teams aren't going to be handing out guarantees to that type of player anymore.
Service-time is going to become less of a concern for all but your top prospects - if you've determined that Shewmake's ceiling is a utility infielder, and he's one that can be helpful while he's cheap, you use him when he can be helpful and take advantage of that. If it's not clear by now that he's a legitimate replacement for Dansby within the next couple of years as he starts to get more and more expensive, you use him to help while it makes sense financially. Platoon him with Riley and use him to give Dansby and Ozzie days off. Shewmake isn't a 17 year old high school kid you didn't know much about when you drafted him, he's got a track record. Look at the Rays' infield - a complete mish-mash of limited ceiling platoon players who play when the matchups are right.
I'm not so sure AA's draft strategy was strictly driven by the lack of money to sign picks. Draft quick-to-the-majors types that can help you soon (Langeliers/Shewmake/Phillip/Kalich), and use them to help with your MLB depth while they're young and inexpensive. If you're not in a position to draft a supposedly "can't-miss" high school kid in the early rounds, why spend tons of money on them? The whiff rate on kids drafted out of high school is much higher than that on college kids. You don't ignore the 17 and 18 year olds with upside (Harris/Grissom/etc.), but if they're not consensus first rounders you don't give them huge bonuses if it's going to take you 4 or 5 years to develop them - there are just too many things that can go wrong.
The list of 2nd and 3rd round college players drafted since 2016 that are already in the majors helping their teams will surprise you...
Keegan Akin (who just shut us down)
Spencer Howard
Griffin Canning
Daulton Varsho
Will Crowe
Nick Solak
Pete Alonso
Garrett Hampson
Sean Murphy
Shaun Anderson
Austin Hays
Aaron Civale
Zac Gallen
Corbin Burnes
Bobby Dalbec
Shane Bieber
Not all of them are "stars", and all have had differing levels of success so far, but their value is that there's a much better chance they turn into useful regulars or bench pieces while they're young if they can make adjustments than there is that you get anything out of the same old boring set of veteran placeholders that keeps getting guaranteed contracts to block them every winter. You wind up holding onto those guys to sit at the end of the bench all year even when you have prospects that are hot because you gave them a couple million dollars. They're a dime-a-dozen and easily replaceable, and there are going to be a ton of veterans available this winter when teams go through their arby-eligible purges.
Teams are much more likely to take a more stars and scrubs approach given where the finances appear to be headed, and if carrying guys like Shewmake and Contreras rather than signing guys like Flowers and Camargo to guaranteed contracts saves you money to chase Bauer, we're probably going to start seeing more of that - particularly from contenders.