I agree, if this is just one accent plant, something more discreet might have been used, but, most taller growing dahlias need a sturdy stake. Dahlias, especially the ones with the large dinner plate blooms become quite top heavy and can topple over or snap especially after a rain or on a windy day. All the dahlia growers I know stake their plants like the one in the picture. Quite often you will see an upturned can on top of these stakes, the cans are stuffed with damp newspaper, one of the best earwig traps there is. One grower I knew collected these cans each morning and shook them out in his chicken pen. When they saw him coming the girls lifted their skirts and came a running.
I was told you gotta sear the stem end with a lighter once you pick them, helps them last longer in the vase somehow. @digitS' would know if this is true as he grows many.
That neighborhood isn't Tobacco Road! And, I thought my orange bailing twine was crude or indiscrete, at best - indelicate.
Serviceable. Bailing twine and 1 by 2's ... Oh, and there's green twine at the garden center.
Searing, I thought, is for keeping vase water clear and fresh longer but it's cotton in the hollow stems for better hydration, according to some dahlia aficionados. I do neither, just change water daily.