As singles, they are nice impulse items. Displaying as groups encourages bulk sales. Ivy's foliage makes for graceful topiary. There are hundreds of varieties available with different leaf colors and shapes. Some varieties and species are adapted to USDA Hardiness Zone 4.
Spider mites are the major pest.
In case of infection, rinse the foliage with a mixture of dish soap and water or with a commercial insecticidal soap. Ivy topiary is best suited for shady areas. Covered patios are ideal.