From cbc.ca:

New research suggests that if consumers want to avoid making impulse purchases, they should refrain from handling goods while shopping, because merely touching an object increases feelings of ownership.

The research, published this week in the Journal of Consumer Research, also found that touching an object, if the experience is pleasant or even neutral, increases how much money consumers would be willing to pay.

Joann Peck, an assistant marketing professor at University of Wisconsin-Madison School of Business, said in an interview that the research has implications for consumers, retailers and advertisers.

"Be very careful when you are shopping: if you don’t want to buy, don’t touch," she said.

"Touch increases your feelings of ownership and it also increases the amount you are willing to pay. I would caution people not to touch when shopping."