There are many things both can learn from each other but the one thing I see most brick and mortar stores ignoring is using a CRM software to collect customer data and then following up with their customers on a regular basis, segment them and tailor campaigns specifically for the segments. Some do a very good job though like Bath & Body Works but most ignore it especially the smaller stores (non-chain stores). It’s not that difficult. Talk to a consulting company like InterloperInc or any other and let them set up your CRM software. There are many good ones like Vtiger, Zoho, SuiteCRM, Sugar, Salesforce, ConstantContact etc. Let the consulting company set it up for you, teach you how to use it and then deploy it. You will be amazed how it can help you get repeat customers.
The toughest thing is making that first sale to a customer. Now that you have, why waste the opportunity of additional sales to the same client month after month, year after year. Get to know him better and reap the rewards.