Lol., story time.
The first time I had tried to make my own tools (finally had enough materials for some copper stuff) I realized that I would have to use cleanse points to do it. Free early skill resets weren’t a thing, then, so I knew immediately that I would need alts to do more than the most basic stuff.
I used some of my early cubits to open a character slot and started a crafter. It seemed a bit painful on the early cubits so used his first cubits to buy another, sort of like ripping off a band-aid 
That made sense and the tutorials and a bit of activity got me another, so I opened another slot and deleted that guy. One by one I dominoed my slots open after that, creating a character, running the tutorials, and buying another slot. In this way my existing characters only ever actually spent cubits on 2 slots, I always had them available when I needed them, and I had a team of 4 “specialist” alts in my first week of gameplay.
Then, I decided to do a sprawling build on Gloviathosa. That’s when I bought a bunch of cubits, and put them on my “harvester” alt. I did that so I could build stuff around a gleam field and my main or my miner could still farm the gleam.
A couple of weeks later they introduced some changes to the plotting and settlement system that really ruined that build’s entire concept.- it became over 90% “road” plots and was bridging in several places, although nobody really knew what was going on at that point.
That issue is what caused me to join the forums and start learning about the more technical side of the game. And after joining the forum is when I was introduced to the concepts of actually farming levels and whatnot, as the table nerf came very shortly after
Anyways those cubits were enough to keep me busy for a while, I’ve never been a really prolific builder. So expanding my very first base was a bit of a struggle but it seemed appropriate so I just went with it until I knew I wanted to make something that, it seemed to me, was honestly a bit large for what I had done in game so far.
At that point I had no problem buying the cubits to do it.
On a side note for the first year I played, my crafter and miner quickly surpassed my main in levels. For the first year and a half or so, Nightstar (my “main”) was usually my third highest leveled character. With the announcement of the ‘upcoming’ skill changes, and the prospect of finally being able to get everything onto one fully competent avatar, I started leveling him almost exclusively.
After all along with many others I wanted to hit that max level requirement before the update dropped 
Since then I backed off of boundless for a long time. Removed all my builds and basically quit for a while. This left me with an excess of plots, actually. I’ve finally started “collecting” cosmetics for my main, and I don’t convert to plots immediately as there may be more use for cubirts in the future.
When I play now it’s normally with a heavy focus on harvesting blocks and materials, and crafting. So like many here, unless there is some drastic change or I get incredibly ambitious, I have plenty of cubits for a long, long time. The 10% plot bonus doesn’t hurt, either.
In a case like @Tmmk’s (forced to switch accounts and lose my characters) I’m not sure - but if I was frustrated with not having enough plots for what I wanted, I would probably buy them again.
Added it early to test the look and make sure it the waterflow doesn’t split somewhere or passes chiseled blocks (because just like light it can pass through blocks that are chiseled on both sides even if there’s no visible gap).
shame 
), reclaimed the beacon of the next character lost a few 100k prestige 
especially if you like mining and gathering 