The Slow Moving Vehicle triangle is just another part of the scenery in most Amish communities. The majority of Amish people willingly use the warning insignia and probably give it little thought. In most places they are such a standard part of the buggy’s appearance, that it is odd to see a vehicle without one.
Some Amish object to the SMV sign however, on grounds including its gaudy colors, and the fact that it is a man-made symbol, suggesting a lack of trust in God’s plan.

A few groups of Amish, notably the Swartzentruber affiliation, simply do not use the triangle. This has led to legal conflict in some places, but generally is accepted in areas where they live.

However, another traditional community has a different solution. The Nebraska Amish settlement at Winfield, Pennsylvania uses the triangle on the road, but then removes it when parked.

Jerry notes:

To my knowledge, Nebraska Amish in other areas (Big Valley and northeastern Ohio) do not do this.

I am told by someone else who would know that this practice is a way to comply while on the road, but the removal of the sign is a symbolic gesture that it’s not a welcome feature on their transportation.
Just another small example of the different worldly accommodations found across Amish society.